A multiple contact switching device for crossbar switches

ABSTRACT

A contact unit for crossbar switches comprises a support body of insulating material of substantially parallelepipedic form carrying fixed contacts and movable contact springs for cooperation with the fixed contacts. The fixed contacts consist of contact bars arranged in a plane parallel to the front and rear surface planes of the body. The movable contact springs are arranged perpendicularly to the plane of the bars which; are fastened to the body at a portion of the same near the rear surface plane and project through slots in the front surface plane. Lifting cards for the contact springs are provided at the movable ends of the springs outside the body.

United States Patent I-Iarald Valdemar Alexandersson Lidingo, SwedenNov. 10, 1969 Oct. 19, 1971 Teleionaktiebolaget LM Ericsson Stockholm,Sweden Dec. 3, 1968 Sweden Inventor Appl. No. Filed Patented AssigneePriority References Cited UNITED STATES PATENTS 12/1951 Knos..200/l66(.1)X

2,587,458 2/1952 Fritts 200/166 (.1)

2,769,880 11/1956 Holmquist et al 200/166 (.1)

3,096,422 7/1963 Alexandersson et al 200/1 66 (.1)

3,480,744 11/1969 Yamada 200/166 (.1 X FOREIGN PATENTS 1,120,020 12/1961Germany 200/166 (.1)

Primary Examiner-H. 0. Jones Att0rneyHane & Baxley ABSTRACT: A contactunit for crossbar switches comprises a support body of insulatingmaterial of substantially parallelepipedic form carrying fixed contactsand movable contact springs for cooperation with the fixed contacts. Thefixed contacts consist of contact bars arranged in a plane parallel tothe front and rear surface planes of the body. The movable contactsprings are arranged perpendicularly to the plane of the bars which; arefastened to the body at a portion of the same near the rear surfaceplane and project through slots in the front surface plane. Liftingcards for the contact springs are provided at the movable ends of thesprings outside the body.

PATENTEDum 19 l97| 3,614,360

INVENTOR BLIMQR "6W ATTORNEY A MULTIPLE CONTACT SWITCHING DEVICE FORCROSSBAR SWITCHES The invention concerns a contact unit for crossbarswitches and the like that comprises fixed contacts in form of parallelbars and movable contact springs for cooperation with these bars,located transversally thereto. In a known device of this kind themovable contact springs are mounted in one assemblage and the fixed barsin another assemblage. The two assemblages are mounted on a common baseplate, so that the movable springs are brought into correct position forcooperation with the bars. This construction requires numerouscomponents and also requires great precision for correct functioning.The invention refers to an improvement and simplification of the knowndevice and is defined in the claims.

The invention will be further described by means of two embodiments withreference to the attached drawing which in H6. 1 shows a cross sectionof the contact unit of one embodiment, and in FIG. 2 shows a partialfront view of this same contact unit, and in FIG. 3 and 4 shows thecorresponding views of second embodiment.

In the device according to FIGS. 1 and 2 a plurality of movable contactsprings 2 are fitted in a body 1 of insulating material, which body hasa substantially rectangular cross section. The contact springs areanchored to the body 1 at a portion adjacent to the rear surface plane 4and project through slots 3 which are widened towards the front surface6 of the body. The contact springs have protruding soldering tags at therear side of the body and in front of the body there is provided alifting card 7 for each spring group, only one of said lifting cardsbeing shown in FIG. 2.

Flxed contact wires 8 are arranged along the front side 6 of the body.They extend along the upper edge of the slots 3 and are in a convenientmanner anchored to the body 1. When a lifting card is actuated, themovable contacts of the corresponding spring group are connected to therespective contact wires 8.

Because a body, such as the onedescribed in this embodiment, may bemanufactured in one piece with all vital dimensions defined by one-halfof a casting tool, the tolerance requirements of the construction areeasily satisfied. The device requires a minimum of details, and a verycompact construction is obtained.

The body I need not necessarily be made in a single solid piece; it canfor example be designed in the way shown in FIGS. 3 and 4. In thisembodiment the body comprises a plurality of substantially equal plates10, each one carrying a contact bar or wire 8, which plates are inconvenient manner fastened to each other, so that they form anessentially compact body 1. The bars 8 are here located in a plane setback from the front plane 6, while the bars in the first describedembodiment are placed in a plane that practically coincides with thefront surface 6.

lclaim:

1. A multiple contact switching device for crossbar switches, saiddevice comprising:

a rigid block made of insulation material and having two parallelsurfaces, said block including a plurality of parallel spaced-apartslots extending between said parallel surfaces;

a plurality of contact bars, one for each slot, said bars stationarilymounted within said slots parallel to the planes of said parallelsurfaces;

an equal plurality of contact springs, each of said springs disposedwithin one of said slots normal to said parallel surfaces, one end ofeach spring secured to the block at a point adjacent to one of saidparallel surfaces and the other end of each spring protruding from theother parallel surface; and

a lifting card disposed outside of said block parallel to said other oneof the parallel surfaces, said card coupled to the protruding ends ofthe springs and lengthwise displaccable for simultaneously moving thesprings into and out of contact with said bars by displacement of thecard. 2. The multiple contact switching devree according to clarm

1. A multiple contact switching device for crossbar switches, saiddevice comprising: a rigid block made of insulation material and havingtwo parallel surfaces, said block including a plurality of parallelspaced-apart slots extending between said parallel surfaces; a pluralityof contact bars, one for each slot, said bars stationarily mountedwithin said slots parallel to the planes of said parallel surfaces; anequal plurality of contact springs, each of said springs disposed withinone of said slots normal to said parallel surfaces, one end of eachspring secured to the block at a point adjacent to one of said parallelsurfaces and the other end of each spring protruding from the otherparallel surface; and a lifting card disposed outside of said blockparallel to said other one of the parallel surfaces, said card coupledto the protruding ends of the springs and lengthwise displaceable forsimultaneously moving the springs into and out of contact with said barsby displacement of the card.
 2. The multiple contact switching deviceaccording to claim 1 wherein said slots are widened toward the endsthereof from which the springs protrude, and said bars are secured toone of the boundary walls of the slots adjacent to the widened endsthereof.
 3. The multiple contact switching device according to claim 1wherein said block is a substantially rectangular block composed of aplurality of parallel plates secured to each other, said slots formedbetween each two adjacent plates.